Set in Derry - but not about the North - Sean O'Reilly's first novel is anintense, evocative and significant debut, enthuses Eileen Battersby

It may imply a lack of cultural patriotism, but there are those who have noticed that much of the more hyped new Irish fiction appears to have been written by comedians. This is not as strange as it seems. Several of these new novelists are professional comedians. But their humour is forced, the books are not funny and the thin plots are predictable. Far more interestingly, the strongest new novel from a younger Irish writer is hardly a comic script at all. Nor is it trying to be one. Yet Love And Sleep, Sean O'Reilly's intense, evocative debut, possesses many flashes of dark, despairing humour, conveyed with a poised understatement - sustained even at moments of narrative excess. For all its bleak apathy and eloquent rage, it is a truthful, possibly profound work worth celebrating. Its power does not surprise, coming less than two years after O'Reilly's debut collection of short stories. Curfew And Other Stories is an impressive performance and includes Rainbows At Midnight, an early version of Love And Sleep, as well as his superbly pitched The Beauty Of Restraint.

In person, O'Reilly (33) is not as intense as his fiction and far less stern than his publicity photograph. Animated, confident and good- naturedly emphatic, he has the appearance of a robust individual who has made his own mistakes and learned to live with them. This is the artist as realist. He has opinions but is not dogmatic and sounds as if he laughs a lot. When he says most Irish fiction is not very good, he is not being clever or dismissive, only saying what he thinks. "I read a lot. I think a writer has to. Most writers don't read nearly enough." Far closer to Eoin McNamee's vision - "Resurrection Man is already a classic" - than to that of John McGahern, he also admires the Scottish writer James Kelman.

Having lived in London,where he was involved in acting with community theatre, and in several other places, including Paris and Norway - "I like to try to live in a place," he says, "I don't run around with a train ticket" - he is currently living in Ireland.

"I came back because there were questions to be answered that I thought I had escaped." On returning from Paris about 18 months ago, he lived briefly in Dublin. It was his first stint living in the city since writing the Curfew stories, between 1997 and 1998, and he admits to finding it a difficult place. "Since October," he says, "I've been living alone in Ballyvaughan, in Co Clare, in a cottage, with two ponies in the field next door."

Though set in Derry, Love And Sleep is not about the North. Nor is it a novel about coming home. It is instead a study of collapse, fear, dislocation and real suffering. Most of all, it is a European novel written by a writer who happens to come from Derry. "I don't see myself as a Northern writer. I'm more interested in form and language, language being the medium I work in as an artist. And that medium has many registers, colloquial and philosophical."

He recalls, as a schoolboy, watching European art-house films, "directors like Fellini, screened late by Channel 4 on Friday night, alone in a sitting room in Derry". The third of six children born into a Bogside Catholic family, O'Reilly has always been drawn to the culture of other parts of Europe, particularly that of Italy, France and Spain. How about Germany? He stops for a moment and looks surprised on admitting he doesn't know much about German culture. "I've never even been to Berlin. Give me a ticket."

Writing was something O'Reilly began early. Initially he wrote plays, film scripts and poetry. "I was very interested in the Irish language," he says. In common with many from the North, he remarks on the narrow southern perception of the North. "It's as if it's all Belfast. It's not. Belfast is as strange to me as it is to a southerner. Coming from Derry, with Donegal to my back, of course I'm Irish." But it seems inappropriate to quiz him about politics, as he is more concerned with the inner lives of his characters and the dreamscapes they inhabit.

What made him leave Ireland? Was it adventure or flight? "About the time of my A levels, I started wondering about things and I left school. That's when I went to London." He later attended the University of East Anglia, where he completed a philosophy degree. Last December, he returned there to be interviewed for a writer's residency. "Guess who was on the interview board. W.G. Sebald. It was two day's before he was killed. A great writer." O'Reilly did not get the post and is still looking for a job.

Love And Sleep owes more to French fiction than it does to any Irish tradition. Its dynamic is more interior than exterior. Niall, the angry, tormented central character and narrator, who tells most but not all of the story, is paralysed by equal measures of apathy, panic and self-disgust. His surroundings, the Derry to which he has returned, are largely irrelevant. Niall's self-absorption is oppressive and his sense of guilt at missing his father's funeral all-consuming. Both, however, are overshadowed by the vicious exactness he brings to his dealings with those near him, particularly the tragic Lorna.

At first, Niall seems an outsider shaped by Camus. But O'Reilly points to another French artist, Georges Bataille (1897-1962), the author of a series of erotic-philosophical novels, including Story Of The Eye. "Bataille was a Dadaist, a surrealist, socialist, capitalist, and I think he was also a mystic."

For O'Reilly, the idea behind Love And Sleep is that life is a random series of acts of sleep, sex and suffering. He sees the eye not so much as a recorder as the instrument through which we experience life. "The eye is the vent through which the self enters and permeates the world," he says. "I don't see the eye as a neutral recorder of the world." O'Reilly's narrative has echoes of Sartre's Nausea as well as of Dostoevsky's Underground Man and the narrator of Knut Hamsun's classic, Hunger. He smiles at this and recalls having once lived in a cottage in Norway, "in Rondane - it's where the Peer Gynt myth comes from; it's even further north than where Hamsun lived".

Niall is no hero. Though a failed writer, he is still aware of language, and all he can offer are lurid details of his sexual encounters. His at times gleeful dismantling of Lorna, the unhappy girl who not so much befriends him as submits to his endless verbal and sexual humiliations, could alienate the reader. Niall's desperate need of her is expressed through sarcasm. Yet O'Reilly's control of the tone and level of Niall's despair ensure he remains unexpectedly sympathetic.

"I'm glad you think that," says O'Reilly with a loud, sudden laugh. "He is suffering and is certainly not walking about Derry making interesting sociological observations about the place." Despite the explicitness of many of his comments, Niall speaks in a distanced first person. O'Reilly agrees that he worked hard to sustain the voice.

There is a hallucinatory, oddly disembodied quality to Niall's monologues. This helps to consolidate the sequences in which the narrative shifts to the third person in order to give further insights into Lorna's dilemma.

In the characterisation of Lorna lies O'Reilly's achievement. She is a disenchanted, overweight art teacher. Having lost out in her previous relationship, she has become involved in socialism. For all her grand gestures and carefully trendy dark clothes, intended to disguise her graceless body, she is insecure, touchingly willing and doomed.

Their biting exchanges culminate in her mounting exasperation with his escapades. "You've told me all that before. About travelling round Spain. Drifting. Begging. For absolutely no reason.Letting yourself fall. And that poor Spanish boy and the knife. And that girl with the white horses in the hills . . . and then that other one, the mad, rich one - on the run from hope, wasn't that what you said? . . . And who else was there? Some English punk and a girl from Norway who lived in caves . . . and some other girl, and then another one who followed you to Italy, jumping trains and stealing, and you had to have sex with her every time she saw a building site or a crane . . . and she vanished into air or something and -"

It's a novel driven more by emotions than by character. Music was the constant that helped sustain the mood and tone through the several drafts it took to write the novel. Still, he accepts that as a writer he is in control of his own "dreamscapes, dream landscapes". Writers, he says with some irritation, play about with time, not geography. "I'm not bound by geography; if I want to set a castle in the middle of the street, I will." Who'd doubt him?

• Love And Sleep is published by Faber & Faber (£9.99 in UK)